The new cultivar is a product of chance discovery. The variety was discovered as a naturally occuring whole plant mutation at a commercial nursery by the inventor, Michel Barrault, a citizen of France. The new variety was discovered among a commercial population of the unpatented variety Gaura lindheimeri ‘Siskyou Pink’, during 2010.
Asexual reproduction of the new cultivar ‘BARGAU’ was first performed by vegetative stem cuttings in Possonniere, France at a commercial nursery. ‘BARGAU’ has since produced more than 5 generations by vegetative cuttings and has shown that the unique features of this cultivar are stable and reproduced true to type.